How exactly does supply work? And how could/should it work?

[CptJackSparrow1993]

I'm trying to gain a deeper understanding of how the supply system works, and how commander traits (i.e., Limited Supply and Chaotic Fire) can impact it. The current system is not terribly well explained as far as I am aware, and I wanted to find out if anyone could tell me more about it. Things like how much fuel and ammo is resupplied each turn by default, when in the turn it happens, how different terrain and weather effects it, does distance from supply hexes have any effect, etc.

Additionally, once we've covered the topic of how supply works in the vanilla game, I'd like to hear some thoughts from community members about how they think the supply system could and/or should work compared to how it currently functions, just as a bit of discussion about a subject I am interested in exploring further.

[VirgilInTheSKY]

When a unit is not surrounded by enemy ZoC (the positive trait that makes your unit neutralize enemy ZoC on its position affects this, note that it does not work on ally units, only your core and aux ones) and terrains impassable for vehicles (high mountains, dense forest, big river and any other terrains that says "blocks supply", bridge unit neutralize the river block) at the start of its turn, it is resupplied with 100% of the max stock it can have. When in bad weather (rain and snow), the resupply amount is cut by half. The negative trait that cut resupply by half is multiplied with the bad weather modifier, so unit would only get a quarter of the max stock if both are present. Other factors has no effect on resupply.

Both Supply Hexes and edges of the map works as a supply provider, so as long as the unit is not cut off from both sources, it is not Encircled (cut off from resupply). Thus a unit sitting on a supply hex or hex at the map edge can never be encircled. Unit with a No Supply hero can be resupplied even in encirclement, that's what that hero does.